On the classification of the order Glires / by Edward R. Alston.
- Edward Richard Alston
- Date:
- 1876
Licence: Public Domain Mark
Credit: On the classification of the order Glires / by Edward R. Alston. Source: Wellcome Collection.
Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.
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![B. Octodontin.e. Grinding-teeth semirooted or rootless, with short and simple enamel-folds. Fur soft. Tail usually short. Ethio- pian and Neotropical. Recent genera :— 3. Petromys, A. Smith, S. African Quart. Journ. ii. p. 2 (1831). Ears short. Fur rather harsh. Pollex very short, with a small nail. Claws short. Tail moderate, rather bushy. Infraorbital opening with a small groove for the nerve. Grinding-teeth semirooted, with single external and internal folds, which nearly meet in the middle. 4. Ctenomys, De Blainville, Bull. Soc. Philomath. 1826, p. 62 (1826). Eye and ear very small. Fur soft. Claws longer than the toes, those of the hind feet with comblike bristles (as in Ctenodactylince). Tail rather short, clad with short hairs. Skull and mandible very massive ; auditory bullae long and pear-shaped ; malar with strong superior and inferior angles ; infraorbital opening with no groove for the nerve. Incisors very broad. Grinding-teeth rootless, with kidney- shaped crowns; the third molar above and below small and sub- circular. 5. Schizodon, Waterhouse, P. Z. S. 1841, p. 91 (1841). External characters much as in Ctenomys, but the ears larger and the claws, th ough strong, not longer than the digits themselves. Skull less massive ; the superior and inferior angles of the malar weaker; infraorbital opening with a groove for the nerve. Incisors broad, convex. Grinding-teeth placed transversely, with single external and internal folds, which meet in the middle. 6. Spalacopus, Wagler, Isis, 1832, p. 1219 (1832). Ear rudimentary; tail short; claws of fore feet shorter than the digits. Skull shorter than in Schizodon ; superior and inferior angles of malar obsolete ; infraorbital opening smaller, with no separate canal for the nerve. Incisors broad, the upper arched boldly for- ward, the lower very long. Grinding-teeth like those of Schizodon ; but the external and internal folds do not meet in the middle line. 7. Octodon, Bennett, P. Z. S. 1832, p. 46 (1832). Ears rather large. Claws small, that of the pollex truncated. Tail long, hairy, bushy at the tip. Skull similar to that of Spalacopus, but with a separate canal in the infraobital opening for the nerve. Incisors narrow. Molars like those of Spalacopus, but placed diago- nally, and the posterior lobe smaller than the anterior in the upper teeth. 8. Habrocoma (= Abrocotna), Waterhouse, P. Z. S. 1837. p. 30 (1837). Ears very large. Fur very soft. Tail moderate, clad with short hairs, not tufted. Pollex obsolete. Skull with the facial portion elongated; malar with moderate superior and inferior angles; auditory bullae very large. Incisors narrow. Upper grinding-teeth with single exter- L31]](https://iiif.wellcomecollection.org/image/b22455334_0035.jp2/full/800%2C/0/default.jpg)
